Blends of thermoplastic polyesters with graft polymers such as ABS and/or rigid polymers are known in the art. For example, the Dieck U.S. Pat. No. 4,280,948, the Hornbaker U.S. Pat. No. 4,397,986, the Binsack et al U.S. Pat. No. 4,535,124, the Heinz et al U.S. Pat. No. 4,666,973, the British Patent Application No. 2,171,705 and West German Reference No. 3,603,185 disclose thermoplastic compositions comprising polyalkylene terephthalate ester polymers and copolymers in combination with graft polymers and/or rigid polymers. The Hornbaker et al U.S. Pat. No. 4,346,195 discloses similar compositions comprising polyethylene terephthalate and a rubber-modified graft copolymer of a vinyl aromatic compound and an .alpha.,.beta.-unsaturated cyclic anhydride, which compositions may further include from about 5 to about 40 percent by weight of one or more impact modifiers. Hornbaker et al further disclose that a preferred impact modifier comprises polyether-ester segmented block copolymers. Japanese References Nos. 57-205442, 58-25356 and 59-11353 disclose additional compositions comprising a polyalkylene terephthalate and a polyether-ester elastomer, and further including a graft copolymer such as ABS and/or a styrene-acrylonitrile copolymer.
The Weemes et al U.S. Pat. No. 4,582,876 discloses blends of copolyether-ester elastomers and rubber-modified styrene-maleic anhydride copolymers having at least two rubbery additives that were present during the polymerization of the copolymers. Japanese Reference No. 59-49255 discloses blends of a maleimide copolymer and a polyether-ester elastomer, a polyether-ester amide and/or polyether amide. The Liu et al U.S. Pat. No. 4,659,765 discloses additional blends of poly(ether ester imide)s, poly(ester imide ethers) and/or poly(ether imide ester)s in combination with a high molecular weight thermoplastic polyester and one or more homopolymers or copolymers derived from vinyl aromatics, esters of acrylic and alkylacrylic acids and/or conjugated dienes. Blends of a copolyether-ester elastomer and a rubber graft polymer such as ABS or MBS are also disclosed in Japanese References Nos. 52-3645, 52-3646, 53-252 and 61-203157.
The Dufour et al U.S. Pat. Nos. 4,460,741 and 4,508,870 and European Patent Applications Nos. 135,493 and 202,615 disclose blend compositions containing a polyether-ester elastomer, a graft polymer such as ABS and a rigid polymer containing styrene and one or more comonomers. These compositions contain relatively low amounts of the polyether-ester elastomer in the range of from about 1 up to 30 weight percent. Finally, the Dufour U.S. Pat. No. 4,500,679 discloses blends of thermoplastic copolyether-ester elastomers, a styrene-maleic anhydride polymer and a rubber graft polymer such as ABS or MBS. The styrene-maleic anhydride polymer may optionally contain from 0 to 20 percent of a termonomer.
These various blends of the prior art exhibit varying combinations of physical properties. Generally, however, one or more good physical properties exhibited by the individual components are deteriorated when the components are blended, whereby the resulting blends exhibit one or more inferior physical properties as compared with the individual components.